In order to realize the object of vehicle lightening, use of a strip having a continuously varying longitudinal thickness manufactured by rolling, VRB (various-thickness rolled blank), is currently under promotion in the vehicle industry.
The rolling technology for manufacture of VRBs is named flexible rolling, originating from a program sponsored by German Research Foundation (DFG) in 1997. As a participant in the program at that time, Mubea Company is the main supplier of VRBs in the present market. The core of the flexible rolling technology is to achieve variation of an exit thickness by adjusting roll gap (see FIG. 1).
For ensuring production efficiency, cold-rolled boards of VRBs are industrially produced in the form of rolls (see FIG. 2).
At a developmental stage of a product, there is usually a need of only a few pieces of VRBs for material property testing, shaping testing, etc. At this time, the form of a roll appears less flexible, not only wasting the material, but also adding subsequent process steps of straightening and cutting.